Springer Online Journal Archives 1860-2000
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Abstract The authors have investigated the effect of the addition of polymeric species (polyethyleneglycol, polypropyleneglycol and polytetramethyleneoxide) containing ether moieties in their main chain on the silica porous structure yielded via the sol-gel method. The obtained silica porous structures were characterized by nitrogen adsorption/desorption and SEM. Introducing those polymeric species apparently enhanced the pore formation. The enhancement is more noticeable for higher concentrations of the polymeric species, distributed from the microporous to mesoporous regions. The pore diameter at which the pore enhancement is induced by adding the polymeric species reduces with the fraction of ether moiety. Adding the polymeric species prior to the onset of the hydrolysis of tetraethylorthosilicate (TEOS) was necessary for the enhancement in the mesoporous region to takes place. The pore enhancement was more outstanding when HCL was used as the catalyst for the hydrolysis of the alkoxide than NH3. The mutual affinity between the added polymeric and silica species is considered as an important factor of the pore generation in the micro- and meso-porous regions.
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